Method and apparatus for configuring link in wireless lan system

ABSTRACT

A method and an apparatus for configuring a link in a wireless LAN system are disclosed. The method for configuring a wireless link comprises: a step of receiving a first beacon message from a first wireless access device through a first communication channel among at least one communication channel; a step of acquiring, from the first communication channel, a first wireless access information to be used for accessing the first beacon message; a step of acquiring, from the first beacon message, a second communication channel list among at least one of the communication channels in which a second wireless access device is operating; a step of determining a communication channel for access among the first and the second communication channels; and a step of attempting access by using the determined communication channel. Therefore, the time for configuring links among wireless LAN devices can be reduced.

TECHNICAL FIELD

A variety of example embodiments according to the present invention generally relate to configuration of a wireless link, and more specifically to methods and devices for rapidly configuring an initial link in a wireless local area networking (WLAN) system.

BACKGROUND ART

Currently, according to wide distribution of mobile stations, a wireless local area networking (WLAN) technology which can provide faster wireless internet services to the mobile stations is becoming remarkable. The WLAN technology is a technology which can make mobile stations such as smart phones, smart pads, laptop computers, portable multimedia players, embedded devices, etc. able to wirelessly access an internet in home, company, or specific service provision areas, based on wireless communication technologies.

DISCLOSURE Technical Problem

The present invention is to provide methods for configuring links between WLAN devices supporting operations in multiple frequency bands.

Also, the present invention is to provide apparatuses for configuring links between WLAN devices supporting operations in multiple frequency bands.

Technical Solution

In order to achieve the purposes of the present invention, according to an example embodiment according to the present invention, a method may be provided for configuring a wireless link, and performed in a mobile station. The method may comprise receiving a first beacon message from a first wireless access station supporting at least one communication channel through a first communication channel among the at least one communication channel; obtaining first wireless access information used for accessing the first communication channel from the first beacon message; obtaining a list including a second communication channel among at least one communication channel supported by a second wireless access station from the first beacon message; determining a communication channel for access among the first communication channel and the second communication channel; and trying to access by using the determined communication channel.

Here, in the trying to access, when the determined communication channel is the first communication channel, authentication may be requested through the first communication channel by using the first wireless access information.

Here, the trying to access may further comprise, when the determined communication channel is the second communication channel, receiving a second beacon message from the second wireless access station through the second communication channel, obtaining second wireless access information used for accessing the second communication channel from the second beacon message; and requesting authentication through the second communication channel by using the second wireless access information.

Here, the trying to access may further comprise, when the determined communication channel is the second communication channel, transmitting a probe request message through the second communication channel; receiving a probe response message from the second wireless access station in response to the probe request message; obtaining second wireless access information used for accessing the second communication channel from the probe response message; and requesting authentication through the second communication channel by using the second wireless access information.

In order to achieve the purposes of the present invention, according to another example embodiment according to the present invention, a method may be provided for configuring a wireless link, and performed in a first wireless access station. The method may comprise generating a first beacon message including first wireless access information used for accessing a first communication channel among the at least one communication channel, and a list including a second communication channel among at least one communication channel supported by a second wireless access station; and transmitting the first beacon message through the first communication channel.

Here, the list may be generated based on information of available communication channels included in at least one of a second beacon message and a probe response message received from the second wireless access station.

Here, the list may be generated based on information of available communication channels included in a message received from the second wireless access station through a distribution system (DS).

In order to achieve another purpose of the present invention, according to an example embodiment according to the present invention, a mobile station may comprise a control part controlling operations of the mobile station; and at least one network interface card for transmitting and receiving data based on commands of the control part. Also, the control part receives a first beacon message from a first wireless access station supporting at least one communication channel through a first communication channel among the at least one communication channel, obtains first wireless access information used for accessing the first communication channel from the first beacon message, obtains a list including a second communication channel among at least one communication channel supported by a second wireless access station from the first beacon message, determines a communication channel for access among the first communication channel and the second communication channel, and tries to access by using the determined communication channel.

Here, when the determined communication channel is the first communication channel, the control part may request authentication through the first communication channel by using the first wireless access information.

Here, when the determined communication channel is the second communication channel, the control part may receive a second beacon message from the second wireless access station through the second communication channel, obtain second wireless access information used for accessing the second communication channel from the second beacon message, and request authentication through the second communication channel by using the second wireless access information.

Here, when the determined communication channel is the second communication channel, the control part may transmit a probe request message through the second communication channel, receive a probe response message from the second wireless access station in response to the probe request message, obtain second wireless access information used for accessing the second communication channel from the probe response message, and request authentication through the second communication channel by using the second wireless access information.

In order to achieve another purpose of the present invention, according to an example embodiment according to the present invention, a wireless access station may comprise a control part controlling operations of first the wireless access station, and at least one network interface card for transmitting and receiving data based on commands of the control part. Also, the control part generates a first beacon message including first wireless access information used for accessing a first communication channel among the at least one communication channel, and a list including a second communication channel among at least one communication channel supported by a second wireless access station, and transmits the first beacon message through the first communication channel.

Here, the list may be generated based on information of available communication channels included in at least one of a second beacon message and a probe response message received from the second wireless access station.

Here, the list may be generated based on information of available communication channels included in a message received from the second wireless access station through a distribution system (DS).

Advantageous Effects

According to example embodiments of the present invention, it becomes possible to reduce a time required for configuring links between WLAN devices supporting operations in multiple frequency bands. Especially, according to example embodiments of the present invention, since communication channel information can be rapidly obtained when links are being configured with a wireless access point using one or more communication channels, the time required for configuring an initial link can be reduced even when a channel through which a mobile station receives a beacon and a channel which the mobile station tries to access is different.

DESCRIPTION OF DRAWINGS

FIG. 1 conceptually illustrates an example configuration of a WLAN system to which embodiments of the present invention can be applied.

FIG. 2 conceptually illustrate a step in which MS configures a link with AP according to an example embodiment of the present invention.

FIG. 3 illustrates a passive scanning step of MS related to an example embodiment of the present invention.

FIG. 4 illustrates an active scanning step of MS related to an example embodiment of the present invention.

FIG. 5 is a block diagram which conceptually illustrates a mobile station (MS) 100 related to an example embodiment of the present invention.

FIG. 6 is a block diagram which conceptually illustrates an access point 200 related to an example embodiment of the present invention.

FIG. 7 is a flow chart illustrating, as an example embodiment of the present invention, a WLAN access procedure in which MS 100 uses only one NIC at a time when MS 100 has multiple NICs 111 and 113 and two or more APs such as AP-1 and AP-2 exist.

FIG. 8 illustrates the example embodiment of FIG. 7 in detail as representing details of messages.

FIG. 9 is a flow chart illustrating, as an example embodiment of the present invention, a WLAN access procedure in which MS 100 receives a beacon message from AP-2 through only one NIC among multiple NICs when MS 100 has multiple NICs 111 and 113 and two or more APs such as AP-1 and AP-2 exist.

FIG. 10 illustrates the example embodiment of FIG. 9 in detail as representing details of messages.

FIG. 11 is a flow chart illustrating, as an example embodiment of the present invention, a WLAN access procedure in which MS 100 receives a probe response message from AP-2 through only one NIC among multiple NICs at a time when MS 100 has multiple NICs 111 and 113 and two or more APs such as AP-1 and AP-2 exist.

FIG. 12 illustrates the example embodiment of FIG. 11 in detail as representing details of messages.

FIG. 13 is a flow chart illustrating, as an example embodiment of the present invention, a WLAN access procedure in which MS 100 simultaneously accesses AP-1 and AP-2 by using two NICs when MS 100 has multiple NICs 111 and 113 and two or more APs such as AP-1 and AP-2 exist.

FIG. 14 illustrates the example embodiment of FIG. 13 in detail as representing details of messages.

FIG. 15 illustrates a packet structure of a beacon message transmitted by AP according to the present invention.

FIG. 16 illustrates a packet structure of a probe request message transmitted by MS according to the present invention.

FIG. 17 illustrates a packet structure of a probe response message transmitted by AP according to the present invention.

MODE FOR INVENTION

Since embodiments described in the present specification are intended to clearly describe the spirit of the present invention to those skilled in the art to which the present invention pertains, the present invention is not limited to those embodiments described in the present specification, and it should be understood that the scope of the present invention includes changes or modifications without departing from the spirit of the invention.

The terms and attached drawings used in the present specification are intended to easily describe the present invention and shapes shown in the drawings are exaggerated to help the understanding of the present invention if necessary, and thus the present invention is not limited by the terms used in the present specification and the attached drawings.

In the present specification, detailed descriptions of known configurations or functions related to the present invention which have been deemed to make the gist of the present invention unnecessarily obscure will be omitted below.

Hereinafter, a method and a device for fast accesses between WLAN devices using a plurality of communication channels according to embodiments of the present invention will be described.

Among standards of WLAN technologies, standardization on Medium Access Control (MAC) and Physical (PHY) layers are going on in an Institute of Electrical and Electronics Engineers (IEEE) 802.11 working group.

FIG. 1 conceptually illustrates an example configuration of a WLAN system to which embodiments of the present invention can be applied.

Referring to FIG. 1, the WLAN system may include one or more basic service sets (BSS) 211 and 221. The BSS 211 or 221 is a set of stations which can communicate with each other, and managed by an access point (AP) 210 or 220. A mobile station (MS) 110 or 120 may perform a role of providing wireless internet services to a user by accessing the AP 210 or 220 according to IEEE 802.11 WLAN standards.

The BSS 211 or 221 may be classified into an infrastructure BSS and an independent BSS, and the infrastructure BSS is illustrated in FIG. 1. The BSS-1 211 is managed and operated by the AP-1 210, and one or more MSs including MS-1 110 and MS-2 120 may receive WLAN services through the AP-1 210. Also, the AP-1 210 is connected to the AP-2 220 through a distribution system (DS) 300. The BSSs 211 and 221 connected through the DS 300 may form an extended service set (ESS) 410. Since the detail of configurations of WLAN systems is described in the standard specifications such as IEEE 802.11-2012 (Mar. 29, 2012), explanation on the detail will be omitted herein. The contents of the standard specifications may be combined to the present description for reference.

FIG. 2 conceptually illustrate a step in which MS configures a link with AP according to an example embodiment of the present invention.

Referring to FIG. 2, a procedure for MS 100 to access AP 200 may comprise three steps—scanning, authentication, and association. The scanning step is a step in which the MS 100 obtains access information of a BSS operated by the AP 200. For the scanning, there are a passive scanning technique S101 that obtains information by using beacon messages which are periodically transmitted by the AP, and an active scanning technique in which the MS transmits a probe request to the AP (S103), receives a probe response from the AP (S105), and obtains access information from the probe response.

The MS 100 which successfully receives the wireless access information in the scanning step may perform the authentication step by transmitting an authentication request (S107 a) and receiving an authentication response (S107 b). After successful completion of the authentication step in the IEEE 802.11 layer, the association step (S109 a and S109 b) may be performed. In addition, authentication based on 802.1X (S111) and a step of obtaining IP address through DHCP (S113) may be performed.

FIG. 3 illustrates a passive scanning step of MS related to an example embodiment of the present invention.

Referring to FIG. 3, the MS-1 110 according to the present invention may obtain wireless access information or respective APs by receiving beacon message which are periodically transmitted by AP-1 210 and AP-2 220 located adjacently.

FIG. 4 illustrates an active scanning step of MS related to an example embodiment of the present invention.

Referring to FIG. 4, the MS-1 110 according to the present invention may transmits a probe request message to obtain information of APs located adjacently, and obtain wireless access information of respective APs by receiving the corresponding probe response messages from AP-1 210 and AP-2 220.

FIG. 5 is a block diagram which conceptually illustrates a mobile station (MS) 100 related to an example embodiment of the present invention.

Referring to FIG. 5, the MS 100 according to the present invention may comprise at least one network interface cards (NIC) 111 to 119 performing a WLAN access through an AP. The network interface cards 111 to 119, modules for performing WLAN access, may be embedded within the MS or installed in outside of the MS. The network interface cards 111 to 119 may perform wireless communications with the AP according to respective supported WLAN specifications. Also, among the network interface cards 111 to 119, only one NIC may operate at a time or a plurality of NICs may simultaneously operate according to performance of the MS 100 or system requirements. In the MS 100 of FIG. 5, the multiple NICs 111 to 119 are illustrated as separated, and MAC and PHY layers of each NIC may operate independently from each other. These NICs 111 to 119 may be implemented as a functional entity which can be separated physically or as a single integrated physical entity.

A mobile communication module 120 may make the MS 100 transmit and receive wireless signals to/from an external device in a mobile communication network.

A user interface part 130 may make commands for controlling the MS 100 be input by a user.

A display part 140 may display results from operations of the MS 100, status of the MS 100, and information provided by the AP.

A memory part 150 may store access program codes for controlling access to the AP, and various data for the program codes.

A control part 160 may perform a role of controlling each of the NICs 111 to 119 to make the MS 100 try to access the AP through an appropriate frequency band by using access information provided by the AP and user/system requirements.

FIG. 6 is a block diagram which conceptually illustrates an access point 200 related to an example embodiment of the present invention.

Referring to FIG. 6, the AP 200 according to the present invention may comprise at least one network interface cards (NIC) 211 to 219 for operating BSS in one or more frequency bands. The network interface cards 211 to 219, modules for performing WLAN access, may be embedded within the AP 200 or installed in outside of the AP 200. The NICs 211 to 219 may perform wireless communications with the MS according to respective supported WLAN specifications. Also, among the network interface cards 211 to 219, only one NIC may operate at a time or a plurality of NICs may simultaneously operate according to performance of the AP 200 or system requirements. In the AP 200 of FIG. 6, a plurality of NICs 211 to 219 are illustrated as separated, and MAC and PHY layers of each NIC may operate independently from each other. These NICs 211 to 219 may be implemented as a functional entity which can be separated physically or as a single integrated physical entity.

A memory part 250 may store access program codes for controlling access from mobile stations, and various data for the program codes.

A control part 260 may perform a role of controlling each of the NICs 211 to 219 to make the AP 200 process access from MS through an appropriate frequency band by using access information for multiple frequency bands and user/system requirements.

FIG. 7 is a flow chart illustrating, as an example embodiment of the present invention, a WLAN access procedure in which MS 100 uses only one NIC at a time when MS 100 has multiple NICs 111 and 113 and two or more APs such as AP-1 and AP-2 exist.

Referring to FIG. 7, the MS 100 may try a WLAN access. First, the AP-1 200 may periodically transmit individual beacon messages to MSs existing in service regions of all BSSs operated by it, in broadcast manner (S101). In this example embodiment, it is assumed that the AP-1 200 transmits a beacon by using the NIC-1 211 (S101).

In this example embodiment, the MS 100 receives the beacon from NIC-1 111 as including BSS information (BSSI, i.e., access information) denoted as 1011 of FIG. 8, operating band (OB) information denoted as 1013 of FIG. 8, and operating channel (OC) information denoted as 1015 of FIG. 8. The BSSI 1011 include access information for the NIC-1 of the AP-1. The OB information 1013 includes frequency ID information of frequency bands operated by NIC-1 311 of the AP-2 300 located adjacently from the AP-1 200. The OC information 1015 includes detailed channel ID number information of frequency bands operated by the NIC-1 311 of the AP-2 300.

The MS 100 receiving the beacon performs at least one step among the following steps through a MS decision step S102. The MS 100 may perform an authentication step to immediately try to access the NIC-1 211 of the AP-1 200 by using BSSI 1011. Alternatively, the MS 100 receiving the beacon may move to a channel operated by NIC-1 311 of AP-2 300, and perform a step of obtaining wireless access information by using the OB information 1013 and the OC information 1015.

In the example embodiment of FIG. 7, it is assumed that access is performed only through NIC-1 213 of AP-1. Then, an authentication step S209 for link configuration and an association step S211 for exchanging association information may be performed with the determined NIC-1 211 of the AP-1 200.

FIG. 8 illustrates the example embodiment of FIG. 7 in detail as representing details of messages.

FIG. 9 is a flow chart illustrating, as an example embodiment of the present invention, a WLAN access procedure in which MS 100 receives a beacon message from AP-2 through only one NIC among multiple NICs when MS 100 has multiple NICs 111 and 113 and two or more APs such as AP-1 and AP-2 exist.

Referring to FIG. 9, the MS 100 may try a WLAN access. First, the AP-1 200 may periodically transmit individual beacon messages to MSs existing in service regions of all BSSs operated by it, in broadcast manner (S101). In this example embodiment, it is assumed that the AP-1 200 transmits a beacon by using the NIC-1 211 (S101).

In this example embodiment, the MS 100 receives the beacon through NIC-1 111 as including BSSI 1011, OB information 1013, and OC information denoted 1015. The BSSI 1011 include access information for the NIC-1 of the AP-1. The OB information 1013 includes frequency ID information of frequency bands operated by NIC-1 311 of the AP-2 300 located adjacently from the AP-1 200. The OC information 1015 includes detailed channel ID number information of frequency bands operated by the NIC-1 311 of the AP-2 300.

The MS 100 receiving the beacon performs at least one step among the following steps through the MS decision step S102. The MS 100 may perform an authentication step to immediately try to access the NIC-1 211 of the AP-1 200 by using BSSI 1011. Alternatively, the MS 100 receiving the beacon may move to a channel operated by NIC-1 311 of AP-2 300, and perform a step of obtaining wireless access information by using the OB information 1013 and the OC information 1015.

In the example embodiment of FIG. 9, it is assumed that the access is performed only through NIC-1 311 of AP-2 300. Then, after receiving a beacon message for configuration of a link with the NIC-1 311 of AP-2 300, an authentication step S209 and an association step S211 may be performed.

FIG. 10 illustrates the example embodiment of FIG. 9 in detail as representing details of messages.

FIG. 11 is a flow chart illustrating, as an example embodiment of the present invention, a WLAN access procedure in which MS 100 receives a probe response message from AP-2 through only one NIC among multiple NICs at a time when MS 100 has multiple NICs 111 and 113 and two or more APs such as AP-1 and AP-2 exist.

Referring to FIG. 11, the MS 100 may try a WLAN access. First, the AP-1 200 may periodically transmit individual beacon messages to MSs existing in service regions of all BSSs operated by it, in broadcast manner (S101). In this example embodiment, it is assumed that the AP-1 200 transmits a beacon by using the NIC-1 211 (S101).

In this example embodiment, the MS 100 receives the beacon through NIC-1 111 as including BSSI 1011, OB information 1013, and OC information denoted 1015. The BSSI 1011 includes access information for the NIC-1 211 of the AP-1 200. The OB information 1013 includes frequency ID information of frequency bands operated by NIC-1 311 of the AP-2 300 located adjacently from the AP-1 200. The OC information 1015 includes detailed channel ID number information of frequency bands operated by the NIC-1 311 of the AP-2 300.

The MS 100 receiving the beacon performs at least one step among the following steps through the MS decision step S102. The MS 100 may perform an authentication step to immediately try to access the NIC-1 211 of the AP-1 200 by using BSSI 1011. Alternatively, the MS 100 receiving the beacon may move to a channel operated by NIC-1 311 of AP-2 300, and perform a step of obtaining wireless access information by using the OB information 1013 and the OC information 1015.

In the example embodiment of FIG. 11, it is assumed that the access is performed only through NIC-1 311 of AP-2 300. Then, after transmitting a probe request message to configure a link with the determined NIC-1 311 of AP-2 300 (S203) and receiving a probe response message corresponding to the probe request message (S205), an authentication step S209 and an association step S211 may be performed.

FIG. 12 illustrates the example embodiment of FIG. 11 in detail as representing details of messages.

FIG. 13 is a flow chart illustrating, as an example embodiment of the present invention, a WLAN access procedure in which MS 100 simultaneously accesses AP-1 and AP-2 by using two NICs when MS 100 has multiple NICs 111 and 113 and two or more APs such as AP-1 and AP-2 exist.

Referring to FIG. 13, the MS 100 may try a WLAN access. First, the AP-1 200 may periodically transmit individual beacon messages to MSs existing in service regions of all BSSs operated by it, in broadcast manner (S101). In this example embodiment, it is assumed that the AP-1 200 transmits a beacon by using the NIC-1 211 (S101).

In this example embodiment, the MS 100 receives the beacon through NIC-1 111 as including BSSI 1011, OB information 1013, and OC information denoted 1015. The BSSI 1011 includes access information for the NIC-1 211 of the AP-1 200. The OB information 1013 includes frequency ID information of frequency bands operated by NIC-1 311 of the AP-2 300 located adjacently from the AP-1 200. The OC information 1015 includes detailed channel ID number information of frequency bands operated by the NIC-1 311 of the AP-2 300.

The MS 100 receiving the beacon performs at least one step among the following steps through the MS decision step S102. The MS 100 may perform an authentication step to immediately try to access the NIC-1 211 of the AP-1 200 by using BSSI 1011. Alternatively, the MS 100 receiving the beacon may move to a channel operated by NIC-1 311 of AP-2 300, and perform a step of obtaining wireless access information by using the OB information 1013 and the OC information 1015.

In the example embodiment of FIG. 13, it is assumed that the MS tries to access the NIC-1 211 of AP-1 200 and the NIC-1 311 of AP-2 300 simultaneously. In case of NIC-1 211 of AP-1 200, an authentication step S109 and an association step S111 may be performed. Then, in order to configure a link with the NIC-1 311 of AP-2 300, the MS may transmit a probe request message (S203), receive a probe response message in response to the probe request message (S205), and perform an authentication step S209 and an association step S211.

FIG. 14 illustrates the example embodiment of FIG. 13 in detail as representing details of messages.

FIG. 15 illustrates a packet structure of a beacon message transmitted by AP according to the present invention.

FIG. 16 illustrates a packet structure of a probe request message transmitted by MS according to the present invention.

FIG. 17 illustrates a packet structure of a probe response message transmitted by AP according to the present invention. 

1. A method of configuring a wireless link, performed in a mobile station, the method comprising: receiving a first beacon message from a first wireless access station supporting at least one communication channel through a first communication channel among the at least one communication channel; obtaining first wireless access information used for accessing the first communication channel from the first beacon message; obtaining a list including a second communication channel among at least one communication channel supported by a second wireless access station from the first beacon message; determining a communication channel for access among the first communication channel and the second communication channel; and trying to access by using the determined communication channel.
 2. The method of claim 1, wherein, in the trying to access, when the determined communication channel is the first communication channel, authentication is requested through the first communication channel by using the first wireless access information.
 3. The method of claim 1, wherein the trying to access further comprises: when the determined communication channel is the second communication channel, receiving a second beacon message from the second wireless access station through the second communication channel; obtaining second wireless access information used for accessing the second communication channel from the second beacon message; and requesting authentication through the second communication channel by using the second wireless access information.
 4. The method of claim 1, wherein the trying to access further comprises: when the determined communication channel is the second communication channel, transmitting a probe request message through the second communication channel; receiving a probe response message from the second wireless access station in response to the probe request message; obtaining second wireless access information used for accessing the second communication channel from the probe response message; and requesting authentication through the second communication channel by using the second wireless access information.
 5. A method of configuring a wireless link, performed in a first wireless access station supporting at least one communication channel, the method comprising: generating a first beacon message including first wireless access information used for accessing a first communication channel among the at least one communication channel, and a list including a second communication channel among at least one communication channel supported by a second wireless access station; and transmitting the first beacon message through the first communication channel.
 6. The method of claim 5, wherein the list is generated based on information of available communication channels included in at least one of a second beacon message and a probe response message received from the second wireless access station.
 7. The method of claim 5, wherein the list is generated based on information of available communication channels included in a message received from the second wireless access station through a distribution system (DS).
 8. A mobile station comprising: a control part controlling operations of the mobile station; and at least one network interface card for transmitting and receiving data based on commands of the control part, wherein the control part receives a first beacon message from a first wireless access station supporting at least one communication channel through a first communication channel among the at least one communication channel, obtains first wireless access information used for accessing the first communication channel from the first beacon message, obtains a list including a second communication channel among at least one communication channel supported by a second wireless access station from the first beacon message, determines a communication channel for access among the first communication channel and the second communication channel, and tries to access by using the determined communication channel.
 9. The mobile station of claim 8, wherein, when the determined communication channel is the first communication channel, the control part requests authentication through the first communication channel by using the first wireless access information.
 10. The mobile station of claim 8, wherein, when the determined communication channel is the second communication channel, the control part receives a second beacon message from the second wireless access station through the second communication channel, obtains second wireless access information used for accessing the second communication channel from the second beacon message, and requests authentication through the second communication channel by using the second wireless access information.
 11. The mobile station of claim 8, wherein, when the determined communication channel is the second communication channel, the control part transmits a probe request message through the second communication channel, receives a probe response message from the second wireless access station in response to the probe request message, obtains second wireless access information used for accessing the second communication channel from the probe response message, and requests authentication through the second communication channel by using the second wireless access information.
 12. A first wireless access station supporting at least one communication channel, the station comprising: a control part controlling operations of first the wireless access station; and at least one network interface card for transmitting and receiving data based on commands of the control part, wherein the control part generates a first beacon message including first wireless access information used for accessing a first communication channel among the at least one communication channel, and a list including a second communication channel among at least one communication channel supported by a second wireless access station, and transmits the first beacon message through the first communication channel.
 13. The method of claim 12, wherein the list is generated based on information of available communication channels included in at least one of a second beacon message and a probe response message received from the second wireless access station.
 14. The method of claim 12, wherein the list is generated based on information of available communication channels included in a message received from the second wireless access station through a distribution system (DS). 